package cn.tedu.sp06.fallback;

import cn.tedu.web.util.JsonResult;
import org.springframework.cloud.netflix.zuul.filters.route.FallbackProvider;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.client.ClientHttpResponse;
import org.springframework.stereotype.Component;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;

/**
 * 通过zuul网关，调用后台商品服务失败的时候会执行这段代码，返回降级结果
 */
@Component
public class ItemFB implements FallbackProvider {
    /**
     * 设置当前降级类是针对哪个服务的降级类
     * item-service:只针对商品服务降级
     * @return
     */
    @Override
    public String getRoute() {
        //当执行item-service失败，
        //应用当前这个降级类
        return "item-service";
        //星号和null都表示所有微服务失败都应用当前降级类
        //"*"; //null;
    }

    //发送给客户端的降级结果 封装在response对象中
    @Override
    public ClientHttpResponse fallbackResponse(String route, Throwable cause) {


        return new ClientHttpResponse() {
            @Override
            public HttpHeaders getHeaders() {
                //Content-Type:application/json;charset=UTF-8
                HttpHeaders httpHeaders = new HttpHeaders();
                httpHeaders.add("Content-Type","application/json;charset=UTF-8");
                return httpHeaders;
            }

            @Override
            public InputStream getBody() throws IOException {
                //JsonResult {code:500,msg:"调用商品服务失败"，data:null}
                String json= JsonResult.err().code(500).msg("调用商品服务失败").toString();
              //String URL="www.baidu.com";
               return new ByteArrayInputStream(json.getBytes("UTF-8"));
              // return new ByteArrayInputStream(URL.getBytes());
            }

            @Override
            public HttpStatus getStatusCode() throws IOException {

                return HttpStatus.INTERNAL_SERVER_ERROR;//{code:500,text:"服务器内部错"}
            }

            @Override
            public int getRawStatusCode() throws IOException {


                return HttpStatus.INTERNAL_SERVER_ERROR.value();//500
            }

            @Override
            public String getStatusText() throws IOException {
                return HttpStatus.INTERNAL_SERVER_ERROR.getReasonPhrase();//"服务器内部错"
            }

            @Override
            public void close() {
            //用来关闭流
                //BAIS不需要关闭
            }
        };
    }
}
